We'll begin with the shocking death of "glee" star cory monteith. An autopsy is scheduled for today and we're hearing from friends and co-stars, abc's neal karlinsky is in vancouver, canada, with the latest on that. Good morning, neal. Reporter: Robin, good morning. This is the hotel where cory monteith died on saturday. You can see some of the flowers and notes that have been left behind. There's still no known cause of death but friends and family are hopeful that autopsy later today will shed some light on this incredibly untimely death. &#9834; Reporter: For millions of fans of the hit tv show "glee" he was fipp, the high school student and football star turned unlikely glee club member who made singing and performing into something cool. &#9834; Well no one told me her &#9834; Reporter: Saturday in downtown vancouver, canada, the person behind the character, 31-year-old cory monteith was found unresponsive in his hotel room after he missed his checkout time. A bright young talent who seemed to have it all, suddenly gone. Paramedics advised the man in the room was clearly deceased. Reporter: Police say foul play is not suspected and according to surveillance cameras and room key records it appears monteith was alone in his room after returning late from a night with friends. According to tmz these are the last known photos of the actor, a week before his death hanging out with friends the day he checked into his vancouver hotel. One of them appears to be holding a beer in her hand. This morning, expressions of grief, co-star matthew morrison dedicating a song to monteith in an off-broadway concert sunday. We lost a great soul and a brother of mine, cory monteith. Reporter: On social media the outpouring was overwhelming from the show's producer, cory was an exceptional talent and we will all miss him tremendously. The list of those posting about their own grief and shock goes on and on. Even the normally stoic police chief -- I watched "glee" regularly with my daughters and I know there will be shock and sadness in many households with the news of this tragic death. Reporter: A cause of death isn't known yet, but a troubled upbringing has left warning signs. I felt like I had to step in at some point and relate to people my experience and rel to people the truth of, you know, my life and where I come from. Reporter: He attended 16 different schools by the time he was 16 when he dropped out. He was a walmart greeter, a cab driver and an addict before turning his life around. Alcohol and drugs the problem? Yeah, absolutely. How old were you? I was about 12 actually. I love you. Reporter: In early 2012 monteith found his love life imitating art when he began dating his on screen girlfriend lea michele. She even talked about the fact that he was so talented and he was so inspiring and motivating for her. Reporter: But earlier this year his old demons seemed to be back. Monteith announced he had checked himself into rehab. Michele stood by him. The two were seen vacationing together after he finished treatment in april. Those closest to him say he had been healthy and happy since getting out, getting ready for a new season of "glee." &#9834; I'm forever yours &#9834; Reporter: Again, the all american always smiling nice guy named finn. &#9834; Faithfully &#9834; he seemed to be doing so well. The show's director said yesterday he spoke with monteith earlier on saturday and that he told him he was doing fantastic. Again, that autopsy later today should shed more light on what went wrong, just a real tragedy, robin. It certainly is and we've been hearing from his loved ones via twitter. Tomorrow we'll hear from one of his 230r78er co-stars. Darren criss will be here. 6-year-old boy swallowed up

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Cory Monteith: Unexpected Loss

Actor Cory Monteith dies unexpectedly in hotel room.

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